Dead zone compensation for touch screens

ABSTRACT

A method of compensated touch data values disclosed herein includes acquiring touch data values about a dead sensing zone of a touch screen, and determining a peak value of those touch data values. Then, a new peak value is calculated as a function of an average of the peak value and another value of the touch data value, and a sharpness value for the dead sensing zone is generated if a second highest value of the touch data values is less than the new peak value. Thereafter, compensated touch data values are generated for the dead sensing zone if the second highest value is greater than the new peak value.

TECHNICAL FIELD

The present disclosure relates generally to touch screens and morespecifically to methods and techniques for compensating touch screensfor dead zones therein.

BACKGROUND

Touch screens are present in many different types of common modernelectronic devices, such as smartphones, tablets, smartwatches,wearables, laptop computers, and so on. In these electronic devices thetouch screen serves as an output device as well as an input device. Thetouch screen typically includes display layer and a sensing layer. Atouch screen controller is coupled to the sensing layer and operates toprocess signals therefrom to detect inputs by a user. The sensing layerincludes touch sensors, and is attached to or formed as an integral partof the display layer, which may be a LCD, IPS, or AMOLED display, forexample.

A typical sensing layer of a touch screen is a capacitive sensor arrayincluding a number of force or drive lines and orthogonally arrangedsense lines. These lines are made from suitable conductive materials,the drive lines are formed on one sub-layer of the sensing layer and thesense lines formed on another sub-layer, with these sub-layers beingseparated by a transparent insulating material such as an insulatingdielectric layer. The overlap of the drive lines and the orthogonallyarranged sense lines with the insulating material between forms an arrayof capacitive sensors. In operation, a drive signal, which is typicallya periodic waveform such as a pulse train, is applied successively tothe drive lines. As the drive signal is applied to a given drive line,the capacitive coupling between that drive line and the sense linesresults in capacitive coupling of the drive signal to the sense lines tothereby generate sense signals on the sense lines responsive to thedrive signal.

The value of the sense signal generated on each sense line is a functionof the capacitive coupling between that sense line and the drive linereceiving the drive signal. This capacitive coupling changes in responseto a user's finger, or other touch device such as a stylus, beingproximate the sensor nodes formed at the overlap of the drive and senselines. This change in capacitive coupling of the drive signal to thesense lines will result in a change in the sense signal generated on thesense lines, and in this way the sense signals indicate whether a user'sfinger or other touch device is adjacent a given sensor node in thetouch panel.

In operation, a user touches a surface of the touch panel or hovers hisor her finger (or a suitable object such as a stylus) above the touchpanel, and the capacitive sensors generate corresponding electronicsensor signals that are provided to the touch screen controller. Fromthese sensor signals, the touch screen controller determines touch datavalues, from the data values determines the type of touch event or hoverevent input by the user to the touch screen, and then provides thisinformation to processing circuitry, such as a system on a chip, in theelectronic device.

Conventional sensing techniques work adequately in the absence ofhardware defects. However, sometimes there may be a hardware defect withone or more capacitive sensors that arises during manufacture, orsometimes after manufacture, for example as a result of stressesundergone by the device. In such situations, conventional sensingtechniques may provide inaccurate results. Thus, new sensing techniquesand/or methods of compensation are needed so as to be able to providefor suitable operation even in the presence of hardware defects.

SUMMARY

A method of compensated touch data values disclosed herein includesacquiring touch data values about a dead sensing zone of a touch screen,and determining a peak value of those touch data values. Then, a newpeak value is calculated as a function of an average of the peak valueand another value of the touch data value, and a sharpness value for thedead sensing zone is generated if a second highest value of the touchdata values is less than the new peak value. Thereafter, compensatedtouch data values are generated for the dead sensing zone if the secondhighest value is greater than the new peak value.

Another method of compensating touch data values disclosed hereinincludes acquiring touch data values about a dead sensing zone of atouch screen, with the touch data values about the dead sensing zonebeing a peak value measured at a first capacitive sensor, an other touchdata value measured at a second capacitive sensor, and a floating valuemeasured at a location between the first and second capacitive sensors.The method also includes generating compensated touch data values forthe dead sensing zone by calculating a centroid of the peak value, thefloating value, the other touch data value, and a further touch datavalue measured at a third capacitive sensor. Differences betweenadjacent ones of the peak value, the floating value, the other touchdata value, and the further touch data value are calculated. Acompensated peak value as a function of the centroid, the peak value,and one of the calculated differences is calculated. A compensatedfloating value is calculated as a function of the centroid, the floatingvalue, and one of the calculated differences. A compensated other valueis calculated as a function of the centroid, the further touch datavalue, and one of the calculated differences.

Another method of compensated touch data values disclosed hereinincludes acquiring touch data values about a dead sensing zone of atouch screen, determining a peak value of the touch data values, andcalculating a new peak value as a function of an average of the peakvalue and another value of the touch data values. A sharpness value isgenerated for the dead sensing zone if a second highest value of thetouch data values is less than the new peak value. A compensatedsharpness value is generated for the dead sensing zone if the secondhighest value is greater than the new peak value. A sharpness value forthe dead sensing zone is replaced with the compensated sharpness valuefor the dead sensing zone if the compensated sharpness value is greaterthan the sharpness value.

A device aspect disclosed herein includes a touch screen formed from aplurality of touch sensors, with the plurality of touch sensorsincluding a plurality of properly functioning touch sensors and at leastone improperly functioning touch sensor, and with the at least oneimproperly functioning touch sensor being capacitively coupled to one ofthe plurality of properly functioning touch sensors. A touch screencontroller is configured for acquiring touch data values about the atleast one improperly functioning touch sensor, determining a peak valueof the touch data values, and calculating a new peak value as a functionof an average of the peak value and another value of the touch datavalues. The touch screen controller is also configured for generating asharpness value for the dead sensing zone if a second highest value ofthe touch data values is less than the new peak value, and generatingcompensated touch data values for the dead sensing zone if the secondhighest value is greater than the new peak value.

Another device aspect disclosed herein includes a touch screencontroller configured for acquiring touch data values about a deadsensing zone of a touch screen, determining a peak value of the touchdata values, and calculating a new peak value as a function of anaverage of the peak value and another value of the touch data values.The touch screen controller is also configured for generating asharpness value for the dead sensing zone if a second highest value ofthe touch data values is less than the new peak value, and generatingcompensated touch data values for the dead sensing zone if the secondhighest value is greater than the new peak value.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an electronic device on which thetechniques described herein may be implemented.

FIG. 1A is a cutaway view of the touch sensitive display of the touchscreen of FIG. 1 showing the components thereof.

FIG. 1B is a schematic block diagram of the touch screen controller ofFIG. 1, and its interconnection with the sense and drive lines of thetouch sensing layer of the touch sensitive display of FIG. 1A.

FIG. 1C illustrates the “dead zones” of the touch sensing layer of thetouch sensitive display of FIG. 1A.

FIG. 2 graph showing the sharpness profile of a live zone of the touchscreen of FIG. 1.

FIG. 3 is a graph showing the sharpness profile of a dead zone of thetouch screen of FIG. 1.

FIG. 4 is a graph showing sensing threshold vs. sharpness of the touchscreen of FIG. 1.

FIG. 5 is a flowchart of a method of compensated touch data values fromthe dead zones of the touch screen of FIG. 1.

FIG. 6 is a graph of touch data values as compensated using the methodsand techniques of FIG. 5.

FIG. 7 is a graph of touch data values as compensated using methods andtechniques described herein.

FIG. 8 is another graph of touch data values as compensated usingmethods and techniques described herein.

DETAILED DESCRIPTION

The present description is made with reference to the accompanyingdrawings, in which example embodiments are shown. However, manydifferent embodiments may be used, and thus the description should notbe construed as limited to the embodiments set forth herein. Rather,these embodiments are provided so that this disclosure will be thoroughand complete. Like numbers refer to like elements throughout.

With initial reference to FIGS. 1-1B an electronic device 100 is nowdescribed. The electronic device 100 may be a smartphone, smartwatch,wearable, tablet, laptop, or other suitable portable electronic device.The electronic device 100 includes a system on a chip 102 that receivesinput from a touch screen controller 106 and provides output to a touchscreen 104.

The touch screen 104 includes a display layer 114, with a touch sensinglayer 116 adjacent thereto. The touch sensing layer 116 includes drivelines D1-D4 that intersect sense lines S1-S4 at some locations. Thesense lines S1-S4 are coupled to the touch screen controller 106, whilethe drive lines D1-D4 are coupled to drive circuitry 118. At eachintersection point between the drive line D1 and the sense lines S1-S4,a capacitance is formed.

In operation, the driving circuitry 118 drives the drive lines D1-D4with periodic signals, such as sine waves or square waves. At certainintersection points between the drive lines D1-D4 and the sense linesS1-S4, touch sensors are formed, the respective sense line S1-S4 incursa charge injection proportional to the voltage at the drive lines D1-D4,and a capacitance between the respective sense line S1-S4 and the drivelines D1-D4 is at the sensor of that intersection point. Thesecapacitances vary in proximity to conductive objects, such as humanfingers and styluses, and are measured by the touch screen controller106 and processed to be touch data values stored in a matrix havingentries that correspond to the various intersections of the drive linesD1-D4 with the force lines S1-S4.

As shown in FIG. 1C, at some intersection points between the driveslines and sense lines, a such touch sensors are not formed, and thecharge injected at the sense line S1-S4 may not be as proportional tothe voltage at the drive line D1-D4 as at the intersection points wheretouch sensors are formed. Thus, the capacitances formed at theseintersection points are not as sensitive to proximity to conductiveobjects, and these intersection points may therefore be referred to as“dead zones”.

As explained, dead sensing zones and live sensing zones are formed intouch sensing layer 116. A graph of sharpness about a live sensing zoneis shown in FIG. 2, whereas a graph of sharpness about a dead sensingzone is shown in FIG. 3. The y axis represents intensity, while the xaxis represents an offset. As is readily apparent, the live sensing zoneincludes alternating points of high and low intensity, with the exampleshown in FIG. 2 having two points below the center line and one pointabove the center line. As is also readily apparent, the dead sensingzone in FIG. 3 includes two points of high intensity and one point oflow intensity, with two points above the center line and one point belowthe center line, and thus lacks the low-high-low alternating pattern ofintensities present in FIG. 2.

Shown in FIG. 4 is a graph of the threshold sensitivity (along they-axis) vs. sharpness (along the x-axis). As can be seen, at a highsensitivity threshold, a finger may still be detected, while a lowsensitivity threshold is used for detection of a stylus. A low sharpnessprovides for a high sensitivity threshold, as shown, while a highsharpness provides for a low sensitivity threshold, as also shown. Theactual sensing is performed at the high intensity points, shown as p2 inFIGS. 2-3. Where the intensity of the sensing point p2 is not muchlarger than the intensity of the surrounding points p1 and p3, thesharpness is low, rendering the dead zones unable to recognize a stylus.Since this would result in missed or inaccurate recognition of touchesand gestures made using a stylus in a dead zone, which would provide fora poor user experience, compensation of the dead zones is desirable.

Such a method or technique for compensation is now taught with referenceto FIG. 5. To start, the touch screen controller 106 acquires touch datavalues about the dead zone (Block 202). Then, a peak data value of theacquired touch data values is determined (Block 204). A new peak is thencalculated as a function of an average of the peak value and anothervalue of the touch data values, for example as (p3+p2)/2 (Block 206). Ifa second highest value of the acquired touch data values if less thanthe new peak (comparison performed at Block 208), then compensation isnot used, and the sharpness is calculated and returned as usual, andoperation proceeds as usual. If, however, the second highest value ofthe acquired touch data values is greater than the new peak (comparisonperformed at Block 208), then compensation is performed resulting in acompensated sharpness (Block 210).

The compensation will now be described with reference to FIG. 6. Firsty1, second y2, and third y3 values are calculated as:y1=p3−p2y2=p2−p1y3=p4−p3.

A center of gravity, or centroid, for the touch data values is thencalculated as:

${centroid} = {{\frac{{p\; 4} - {p\; 2}}{{p\; 3} + {\max\left( {{p\; 2},{p\; 4}} \right)}} - {2*{\min\left( {{p\; 2},{p\; 4}} \right)}}}}$

Using the centroid, a first compensated data value is calculated as:N1=p2−(y2*centroid)

An intermediate value used in calculating a second compensated value isthen calculated as:N′=p3−(y1*centroid)

Now, the second compensated data value is calculated as:N2=N′+(N′*centroid)

Then, a third compensated data value is calculated as:N3=p4−(y3*centroid)

These compensated data values replace the acquired data values, thusproviding for a sharpness profile, as shown in FIG. 5, that permitssensing of a stylus in a dead zone. The compensated sharpness can becalculated as:sharpness=2*N2−(N1+N3).

As can be seen in FIG. 5, application of the compensation to the touchdata values provides for a sharpness profile capable of recognizingstylus inputs in the dead zone.

In some instances, adequate results may still be obtained withoutperforming all steps as above, or without performing the same steps asabove. For example, the intermediate value may be used as the secondcompensated data value, resulting in the graph shown in FIG. 8.

As another example, the new peak calculated at Block 206 can be used asthe second compensated data value, with the first and second compensateddata values being p1 and p4, respectively. The resulting graph ofcompensated data values using this is shown in FIG. 7.

Each of the steps performed above may be performed in a period of timequicker than a human is capable of, such as in under 1 second, or evenunder 0.5 second, or even under 0.1 second. It should be appreciatedthat the touch screen controller 106 is a specific purpose computingdevice, with transistors and/or logic gates specifically programmed soas to carry out the techniques described herein. Thus, the touch screencontroller 106 contains measurable and observable physical differencesover an unprogrammed generic purpose computer or processor. It shouldalso be understood that the techniques described herein necessarilyarise out of touch screen technology—that is, absent the existence ofcapacitive touch screens, the techniques herein would not exist. Thus,these techniques are not directed to disembodied information processing,but are instead directed to the determination of the spatialrelationship between two physical objects, the stylus and the touchscreen. Moreover, these techniques improve the performance of the touchscreen technology to which they are applied, increasing the precisionand accuracy of the touch detection performed by the touch screen.

Many modifications and other embodiments will come to the mind of oneskilled in the art having the benefit of the teachings presented in theforegoing descriptions and the associated drawings. Therefore, it isunderstood that various modifications and embodiments are intended to beincluded within the scope of the appended claims.

The invention claimed is:
 1. A method, comprising: acquiring touch datavalues about a dead sensing zone of a touch screen, wherein the touchdata values about the dead sensing zone comprise a peak value measuredat a first capacitive sensor, an other touch data value measured at asecond capacitive sensor, and a floating value measured at an areabetween the first and second capacitive sensors, and; generatingcompensated touch data values for the dead sensing zone by: calculatinga centroid of the peak value, the floating value, the other touch datavalue, and a further touch data value measured at a third capacitivesensor; calculate differences between adjacent ones of the peak value,the floating value, the other touch data value, and the further touchdata value; calculate a compensated peak value as a function of thecentroid, the peak value, and one of the calculated differences;calculate a compensated floating value as a function of the centroid,the floating value, and one of the calculated differences; and calculatea compensated other value as a function of the centroid, the furthertouch data value, and one of the calculated differences.
 2. The methodof claim 1, wherein the touch data values about the dead sensing zonecomprise first (p1), second (p2), third (p3), and fourth (p4) touch datavalues.
 3. The method of claim 2, wherein the centroid of the peakvalue, the floating value, the other touch data value, and a furthertouch data value measured at a third capacitive sensor is calculated by:calculating a first value y1=p3−p2; calculating a second value y2=p2−p1;calculating a third value y3=p4−p3; calculating the centroid${centroid} = {{{\frac{{p\; 4} - {p\; 2}}{{p\; 3} + {\max\left( {{p\; 2},{p\; 4}} \right)}} - {2*{\min\left( {{p\; 2},{p\; 4}} \right)}}}}.}$4. The method of claim 3, wherein the compensated peak value iscalculated by: calculating an intermediate value N′=p3−(y1*centroid);and calculating a second compensated data value N2=N′+(N′*centroid). 5.The method of claim 3, wherein the compensated floating value iscalculated by: calculating a first compensated data valueN1=p2−(y2*centroid).
 6. The method of claim 3, wherein the compensatedother value is calculated by: calculating a third compensated data valueN3=p4−(y3*centroid).
 7. A method, comprising: acquiring touch datavalues about a dead sensing zone of a touch screen; determining a peakvalue of the touch data values; calculating a new peak value as afunction of an average of the peak value and another value of the touchdata values; generating a sharpness value for the dead sensing zone if asecond highest value of the touch data values is less than the new peakvalue; and generating compensated touch data values for the dead sensingzone if the second highest value is greater than the new peak value. 8.The method of claim 7, wherein the touch data values about the deadsensing zone comprise the peak value measured at a first capacitivesensor, an other touch data value measured at a second capacitivesensor, and a floating value measured at a location between the firstand second capacitive sensors.
 9. The method of claim 8, wherein thecompensated touch data values are generated by: calculating a centroidof the peak value, the floating value, the other touch data value, and afurther touch data value measured at a third capacitive sensor;calculate differences between adjacent ones of the peak value, thefloating value, the other touch data value, and the further touch datavalue; calculate a compensated peak value as a function of the centroid,the peak value, and one of the calculated differences; calculate acompensated floating value as a function of the centroid, the floatingvalue, and one of the calculated differences; and calculate acompensated other value as a function of the centroid, the further touchdata value, and one of the calculated differences.
 10. The method ofclaim 7, wherein the touch data values about the dead sensing zonecomprise first (p1), second (p2), third (p3), and fourth (p4) touch datavalues.
 11. The method of claim 10, wherein the compensated touch datavalues are generated by: calculating a first value y1=p3−p2; calculatinga second value y2=p2−p1; calculating a third value y3=p4−p3; calculatinga centroid${{centroid} = {{\frac{{p\; 4} - {p\; 2}}{{p\; 3} + {\max\left( {{p\; 2},{p\; 4}} \right)}} - {2*{\min\left( {{p\; 2},{p\; 4}} \right)}}}}};$calculating a first compensated data value N1=p2−(y2*centroid);calculating an intermediate value N′=p3−(y1*centroid); calculating asecond compensated data value N2=N′+(N′*centroid); calculating a thirdcompensated data value N3=p4−(y3*centroid).
 12. A method, comprising:acquiring touch data values about a dead sensing zone of a touch screen;determining a peak value of the touch data values; calculating a newpeak value as a function of an average of the peak value and anothervalue of the touch data values; generating a sharpness value for thedead sensing zone if a second highest value of the touch data values isless than the new peak value; generating a compensated sharpness valuefor the dead sensing zone if the second highest value is greater thanthe new peak value; and replacing a sharpness value for the dead sensingzone with the compensated sharpness value for the dead sensing zone ifthe compensated sharpness value is greater than the sharpness value. 13.The method of claim 12, wherein the touch data values about the deadsensing zone comprise first (p1), second (p2), third (p3), and fourth(p4) touch data values.
 14. The method of claim 13, wherein thecompensated sharpness value is generated by: calculating a first valueas a function of the second and third touch data values; calculating asecond value as a function of the first and second touch data values;calculating a third value as a function of the third and fourth touchdata values; calculating a centroid as a function of the second, third,and fourth touch data values; calculating a first compensated data valueas a function of the second touch data value, second value, and thecentroid; calculating a second compensated data value as a function ofthe third touch data value, the first value, and the centroid;calculating a third compensated data value as a function of the fourthtouch data value, the third value, and the centroid; and calculating thecompensated sharpness value as a function of the first, second, andthird compensated data values.
 15. The method of claim 13, wherein thecompensated sharpness value is generated by: calculating a first valuey1=p3−p2; calculating a second value y2=p2−p1; calculating a third valuey3=p4−p3; calculating a centroid${{centroid} = {{\frac{{p\; 4} - {p\; 2}}{{p\; 3} + {\max\left( {{p\; 2},{p\; 4}} \right)}} - {2*{\min\left( {{p\; 2},{p\; 4}} \right)}}}}};$calculating a first compensated data value N1=p2−(y2*centroid);calculating an intermediate value N′=p3−(y1*centroid); calculating asecond compensated data value N2=N′+(N′*centroid); calculating a thirdcompensated data value N3=p4−(y3*centroid); and calculating thecompensated sharpness value sharpness=2*N2−(N1+N3).
 16. The method ofclaim 12, wherein the touch data values about the dead sensing zonecomprise the peak value measured at a first capacitive sensor, an othertouch data value measured at a second capacitive sensor, and a floatingvalue measured at a location between the first and second capacitivesensors.
 17. The method of claim 16, wherein the compensated sharpnessvalue is generated by: calculating a centroid of the peak value, thefloating value, the other touch data value, and a further touch datavalue measured at a third capacitive sensor; calculate differencesbetween adjacent ones of the peak value, the floating value, the othertouch data value, and the further touch data value; calculate acompensated peak value as a function of the centroid, the peak value,and one of the calculated differences; calculate a compensated floatingvalue as a function of the centroid, the floating value, and one of thecalculated differences; calculate a compensated other value as afunction of the centroid, the further touch data value, and one of thecalculated differences; calculate the compensated sharpness value as afunction of the compensated peak value, the compensated floating value,and the compensated other value.
 18. An electronic device, comprising: atouch screen comprising a plurality of touch sensors, the plurality oftouch sensors including a plurality of live touch sensors and at leastone dead sensing zone, the at least one dead sensing zone beingcapacitively coupled to one of the plurality of live touch sensors; anda touch screen controller configured for: acquiring touch data valuesabout the at least one dead sensing zone; determining a peak value ofthe touch data values; calculating a new peak value as a function of anaverage of the peak value and another value of the touch data values;generating a sharpness value for the at least one dead sensing zone if asecond highest value of the touch data values is less than the new peakvalue; and generating compensated touch data values for the at least onedead sensing zone if the second highest value is greater than the newpeak value.
 19. The electronic device of claim 18, wherein the touchdata values about the at least one dead sensing zone comprise the peakvalue measured at a first capacitive sensor, an other touch data valuemeasured at a second capacitive sensor, and a floating value measured ata location between the first and second capacitive sensors.
 20. Theelectronic device of claim 19, wherein the touch screen controllergenerates the compensated touch data values by: calculating a centroidof the peak value, the floating value, the other touch data value, and afurther touch data value measured at a third capacitive sensor;calculate differences between adjacent ones of the peak value, thefloating value, the other touch data value, and the further touch datavalue; calculate a compensated peak value as a function of the centroid,the peak value, and one of the calculated differences; calculate acompensated floating value as a function of the centroid, the floatingvalue, and one of the calculated differences; and calculate acompensated other value as a function of the centroid, the further touchdata value, and one of the calculated differences.
 21. An electronicdevice, comprising: a touch screen controller configured to: acquiretouch data values about a dead sensing zone of a touch screen; determinea peak value of the touch data values; calculate a new peak value as afunction of an average of the peak value and another value of the touchdata values; generate a sharpness value for the dead sensing zone if asecond highest value of the touch data values is less than the new peakvalue; generate a compensated sharpness value for the dead sensing zoneif the second highest value is greater than the new peak value; andreplace a sharpness value for the dead sensing zone with the compensatedsharpness value for the dead sensing zone if the compensated sharpnessvalue is greater than the sharpness value.
 22. The electronic device ofclaim 21, wherein the touch data values about the dead sensing zonecomprise first (p1), second (p2), third (p3), and fourth (p4) touch datavalues.
 23. The electronic device of claim 22, wherein touch screencontroller is configured to generate the compensated sharpness value by:calculating a first value as a function of the second and third touchdata values; calculating a second value as a function of the first andsecond touch data values; calculating a third value as a function of thethird and fourth touch data values; calculating a centroid as a functionof the second, third, and fourth touch data values; calculating a firstcompensated data value as a function of the second touch data value,second value, and the centroid; calculating a second compensated datavalue as a function of the third touch data value, the first value, andthe centroid; calculating a third compensated data value as a functionof the fourth touch data value, the third value, and the centroid; andcalculating the compensated sharpness as a function of the first,second, and third compensated data values.
 24. The electronic device ofclaim 22, wherein touch screen controller is configured to generate thecompensated sharpness value by: calculating a first value y1=p3−p2;calculating a second value y2=p2−p1; calculating a third value y3=p4−p3;calculating a centroid${{centroid} = {{\frac{{p\; 4} - {p\; 2}}{{p\; 3} + {\max\left( {{p\; 2},{p\; 4}} \right)}} - {2*{\min\left( {{p\; 2},{p\; 4}} \right)}}}}};$calculating a first compensated data value N1=p2−(y2*centroid);calculating an intermediate value N′=p3−(y1*centroid); calculating asecond compensated data value N2=N′+(N′*centroid); calculating a thirdcompensated data value N3=p4−(y3*centroid); and calculating thecompensated sharpness value sharpness=2*N2−(N1+N3).
 25. The electronicdevice of claim 21, wherein the touch data values about the dead sensingzone comprise the peak value measured at a first capacitive sensor, andan other touch data value measured at a second capacitive sensor, and afloating value measured at a location between the first and secondcapacitive sensors.
 26. The electronic device of claim 25, wherein thetouch screen controller is configured to generate the compensatedsharpness value by: calculating a centroid of the peak value, thefloating value, the other touch data value, and a further touch datavalue measured at a third capacitive sensor; calculate differencesbetween adjacent ones of the peak value, the floating value, the othertouch data value, and the further touch data value; calculate acompensated peak value as a function of the centroid, the peak value,and one of the calculated differences; calculate a compensated floatingvalue as a function of the centroid, the floating value, and one of thecalculated differences; calculate a compensated other value as afunction of the centroid, the further touch data value, and one of thecalculated differences.
 27. An electronic device, comprising: a touchscreen controller configured for: acquiring touch data values about adead sensing zone of a touch screen; determining a peak value of thetouch data values; calculating a new peak value as a function of anaverage of the peak value and another value of the touch data values;generating a sharpness value for the dead sensing zone if a secondhighest value of the touch data values is less than the new peak value;and generating compensated touch data values for the dead sensing zoneif the second highest value is greater than the new peak value.
 28. Theelectronic device of claim 27, wherein the touch data values about thedead sensing zone comprise the peak value measured at a first capacitivesensor, an other touch data value measured at a second capacitivesensor, and a floating value measured at a location between the firstand second capacitive sensors.
 29. The electronic device of claim 28,wherein touch screen controller generates the compensated touch datavalues by: calculating a centroid of the peak value, the floating value,the other touch data value, and a further touch data value measured at athird capacitive sensor; calculate differences between adjacent ones ofthe peak value, the floating value, the other touch data value, and thefurther touch data value; calculate a compensated peak value as afunction of the centroid, the peak value, and one of the calculateddifferences; calculate a compensated floating value as a function of thecentroid, the floating value, and one of the calculated differences; andcalculate a compensated other value as a function of the centroid, thefurther touch data value, and one of the calculated differences.
 30. Theelectronic device of claim 27, wherein the touch data values about thedead sensing zone comprise first (p1), second (p2), third (p3), andfourth (p4) touch data values.
 31. The electronic device of claim 30,wherein the touch screen controller generates the compensated touch datavalues by: calculating a first value y1=p3−p2; calculating a secondvalue y2=p2−p1; calculating a third value y3=p4−p3; calculating acentroid${{centroid} = {{\frac{{p\; 4} - {p\; 2}}{{p\; 3} + {\max\left( {{p\; 2},{p\; 4}} \right)}} - {2*{\min\left( {{p\; 2},{p\; 4}} \right)}}}}};$calculating a first compensated data value N1=p2−(y2*centroid);calculating an intermediate value N′=p3−(y1*centroid); calculating asecond compensated data value N2=N′+(N′*centroid); calculating a thirdcompensated data value N3=p4−(y3*centroid); calculate the compensatedsharpness as a function of the first, second, and third compensated datavalues.